On http://www.d-programming-language.org/rdmd.html Andrei states:
(Under Windows replace cat with type and #!/usr/bin/rdmd with #!rdmd, the
latter assuming that rdmd can be found in your path.)
what is the #!rdmd about ? I know of no windows shebang syntax, and trying it
it a batch file, and in a .d file yielded no results.
rdmd is in the path. Win 7. ran .bat and .d files both from windows shell and
a cmd prompt.
dont really need it, but I know Andrei is usually pretty precise about these
kind of things - and it peaked my curiosity. maybe in MSDOS it worked ?

dont really need it, but I know Andrei is usually pretty
precise about these
kind of things - and it peaked my curiosity. maybe in MSDOS it
worked ?

No, MS-DOS used extensions like Windows.
Shebang makes sense if you try to run a D program from a
bash-like shell, e.g. using MSys or CygWin. It'd make sense to
look for rdmd in the PATH (as opposed to passing an absolute
path), assuming that'll work at all. Replacing cat with type
seems odd, though, since using a shebang-aware shell implies that
other Unix-like tools are available, like cat.